Rotation of a shaft of a motor through a desired number of angular increments can be effected by increasing the count in an error register with a number of pulses equal to the number of angular increments through which the motor is to be rotated and decreasing the count in the error register by one each time a motor passes through an angular increment. The angular increments through which the motor passes can be determined by noting when markers that rotate with the motor pass through a given reference point. The net absolute count in the error register is transferred to a D/A converter and a voltage proportional to its output is applied to the motor. When the net count reaches zero, no voltage is applied to the motor. If the system is critically damped or other control means are provided, the motor will come to rest just after turning through the last angular increment. However, when the system has some degree of elasticity combined with some static friction, such as would occur, for example, if the motor were coupled to its load by a rubber belt, a restoring force exists that may rotate the motor in the opposite direction after it has reached the desired position and cause a marker of an angular increment to pass back through the reference point. This introduces a count into the error register that reverses the rotation of the motor and causes the marker to pass again through the reference point in the original direction. The process can be repeated so as to produce hunting that causes an audible hum and consumes power.